Season chicken with1 tsp ginger powder, 1 tsp garlic powder, onion powder, white pepper, and salt. Leave to marinate for 30 minutes.
In three separate bowls, put (1) 1 cup flour and 1 tsp garlic powder; (2) 2 eggs mixed; (3) 1 cup breadcrumbs
Dip each piece of chicken into bowls 1, then 2, then 3 and place in baking tray lined with parchment paper or cooling rack. Refill bowls with ingredients as necessary.
Pre-heat oven to 400 degrees F
Spray chicken with oil and bake for 30-45 minutes until internal temperature >= 165 degrees F. You may want to turn the chicken pieces over halfway.
If using air fryer, put pieces into air fryer and spray with oil. Air fry at 375 degrees F for 10 minutes. Turn pieces over, spray with oil and air fry for another 2 minutes.
To make tonkatsu sauce, mix together: ketchup, soy sauce, brown sugar, apple cider vinegar, Worcestershire sauce, 1 tsp ginger powder and 1 tbsp garlic powder.